MGRS or MGUS? Diagnostic Dilemma of ANCA-Associated Pauci-Immune Crescentic Glomerulonephritis with Monoclonal Gammopathy: A Case Report

This case underscores the importance of integrating serological, histopathological, and advanced imaging techniques to distinguish between autoimmune and plasma cell dyscrasias in renal pathology. It also emphasizes the limitations of immunofluorescence alone in diagnosing MGRS and the necessity of immuno-electron microscopy for definitive exclusion. This report calls for further research into the pathophysiological interactions between ANCA-associated vasculitis and monoclonal gammopathies, particularly in cases with overlapping renal injury features.